μύσις
From LSJ
πολλὰ μεταξὺ πέλει κύλικος καὶ χείλεος ἄκρου → there is many a slip twixt cup and lip, there's many a slip twixt cup and lip, there's many a slip 'twixt cup and lip, there's many a slip twixt the cup and the lip, there's many a slip 'twixt the cup and the lip
English (LSJ)
[ῠ], εως, Ion. ιος, ἡ, (μύω)
A closing, ὑστέρης Aret.SD2.1, cf. Dsc.1.32 (pl.); στομίων, στομάχου, πόρων, Gal.6.218,7.249,10.602.
German (Pape)
[Seite 222] ἡ, das Zusammendrücken, Schließen des Mundes, der Augen u. anderer Dinge, Sp.
Greek (Liddell-Scott)
μύσις: [ῠ], εως, ἡ, (μύω) τὸ κλείειν τὰ χείλη, τοὺς ὀφθαλμούς, κτλ., Ἐκκλ.· ἐπὶ τῆς μήτρας, Ἀρετ. π. Αἰτ. Χρον. Παθ. 2. 1. ΙΙ. (ἐκ τοῦ παθ.), τὸ νὰ εἶναί τις κεκλεισμένος, ἔμφραξις, ἐπὶ τῶν πόρων, τῶν ἐντοσθίων, κτλ. Ἰατρ.